You need to consume adequate amounts of protein at each meal of the day to keep your muscles at their best, a new study shows.
But many Americans get uneven amounts of protein, with too little at breakfast and lunch and too much at dinner, according to the researchers at the University of Texas Medical Branch at Galveston.
Their study included healthy adults who ate similar diets that distributed a total of 90 grams of protein intake differently throughout the day. One diet provided 30 grams of protein at each meal, while the other provided 10 grams at breakfast, 15 grams at lunch and 65 grams at dinner. Lean beef was the primary source of protein in both diets.
Ninety grams of protein is the average daily amount consumed by Americans. The recommended daily amount is about 60 grams.
Muscle protein synthesis was 25 percent higher among participants who ate the diet with evenly distributed protein intake, compared with those who ate the diet with greater variation in protein intake, according to the study published online May 20 in the Journal of Nutrition.
"Usually, we eat very little protein at breakfast, a bit more at lunch and then consume a large amount at night. When was the last time you had just 4 ounces of anything during dinner at a restaurant?" study leader and muscle metabolism expert Doug Paddon-Jones said in a university news release.
"So we're not taking enough protein on board for efficient muscle building and repair during the day, and at night we're often taking in more than we can use. We run the risk of having this excess oxidized and ending up as glucose or fat," he explained.
Many Americans would benefit from evening out their daily protein consumption, the researchers said.
"You don't have to eat massive amounts of protein to maximize muscle synthesis, you just have to be a little more thoughtful with how you apportion it," Paddon-Jones said.
"For breakfast, consider replacing some carbohydrate, particularly the simple sugars, with high-quality protein," Paddon-Jones said. "Throw in an egg, a glass of milk, yogurt or add a handful of nuts to get closer to 30 grams of protein; do something similar to get to 30 for lunch, and then moderate the amount of protein for dinner. Do this, and over the course of the day you will likely spend much more time synthesizing muscle protein."